• South African clocks 43.98sec to finish well clear of Steve Gardiner• Medical team hits out at IAAF decision to turn away Botswanan

Wayde van Niekerk completed the first stage of what he hopes will be a glorious London double by storming to victory in the men’s 400m – but the night was mired in controversy and bitterness after his main rival, Isaac Makwala of Botswana, was barred from running by the sport’s governing body, the IAAF.

Van Niekerk is known for throwing up after his races, such is the all-out effort he puts in when he runs. But the South African was able to win easing down in 43.98sec, nearly a half a second clear of Steve Gardiner of the Bahamas, with the Qatari Abdalelah Haroun finishing incredibly quickly to take bronze in 44.48.